Starting DataStax Enterprise as a service 

Starting the DataStax Enterprise service when DataStax Enterprise was installed from the DataStax Installer with the Services option or from a RHEL or Debian package.

Steps for starting the DataStax Enterprise service when DataStax Enterprise was installed from the DataStax Installer with the Services option or from a RHEL or Debian package.

Note: All nodes types are DataStax Enterprise nodes and run the Cassandra database.

Considerations 

Be aware of the following when starting a cluster:

Nodes must be segregated by datacenters 
With the exception of SearchAnalytics nodes, transactional (Cassandra), DSE Search, and DSE Analytics nodes must be in separate datacenters. For example, in a cluster with both DSE Search and transactional nodes, all DSE Search nodes must be in a one or more search datacenters and all transactional nodes must be in one or more Cassandra datacenters.
Note: DSE Graph can be enabled in any datacenter as long as it's enabled on every node within the datacenter.
Deploying a mixed-workload cluster 
When deploying one or more datacenters for each type of node, first determine which nodes to start as transactional, analytic, DSE Graph only, DSE Graph plus other types, and DSE Search nodes. Deploy in this order:
  1. Analytic seed nodes.
  2. Cassandra or DSE Graph only seed nodes.
  3. DSE Search seed nodes.
  4. Remaining nodes one at a time. See Multiple datacenter deployment.
Attention: When using DSE Hadoop, do not start all the nodes at the same time, as this causes contention among Hadoop nodes to become the Job Tracker.
DSE Analytics nodes 
Before starting DSE Analytics nodes, ensure that the replication factor is configured correctly for the analytics keyspaces. Every time you add a new datacenter, you must manually increase the replication factor of the dse_leases keyspace for the new DSE Analytics datacenter.

Start up commands

Set the type of node in the /etc/default/dse file. (Startup scripts are also available in /etc/init.d.)
Command Description
GRAPH_ENABLED=1 Starts the node as a DSE Graph node.
SPARK_ENABLED=1 Starts the node as a Spark node and starts the Spark Master service.
SOLR_ENABLED=1 Starts the node as a DSE Search node.
HADOOP_ENABLED=1 Designates the node as a DSE Hadoop node and starts the Hadoop Job Tracker and Task Tracker services.
Note: DSE Graph is not supported with Hadoop.
Cassandra-only, BYOH, or BYOS nodes NODE_TYPES=0 or not present.
Examples
Node type Settings
Spark Analytics node
SPARK_ENABLED=1
SOLR_ENABLED=0
GRAPH_ENABLED=0
HADOOP_ENABLED=0
or
SPARK_ENABLED=1
Note: No entry is the same as disabling it.
Spark Analytics, DSE Graph, and DSE Search node
SPARK_ENABLED=1
GRAPH_ENABLED=1
SOLR_ENABLED=1
BYOS (Bring Your Own Spark)

Spark nodes run in separate Spark cluster from a vendor other than DataStax.

Set BYOS nodes as Cassandra nodes:

All_NODE_TYPES=0 or not present.

DSE Graph and BYOS
GRAPH_ENABLED=1
DSE Graph and BYOH (DSE Graph with Bring Your Own Hadoop)

Hadoop nodes run in separate Hadoop cluster from a vendor other than DataStax.

GRAPH_ENABLED=1
SearchAnalytics nodes

An integrated DSE SearchAnalytics cluster allows analytics jobs to be performed using search queries.

SPARK_ENABLED=1
SOLR_ENABLED=1
DSE Hadoop
HADOOP_ENABLED=1
DSE Hadoop uses Hadoop 1.0.4 libraries uses built-in Hadoop Job Trackers and Task Trackers.
DSE Graph and DSE Hadoop Not supported.
GRAPH_ENABLED=1
HADOOP_ENABLED=1

Prerequisites

Be sure to read the Considerations.

Procedure

If DataStax Enterprise is running, stop the node.

Note: You can also use OpsCenter to start and stop nodes.

  1. Set the node type in the /etc/default/dse file. For example, to a Spark node:
    SPARK_ENABLED=1
    SOLR_ENABLED=0
    GRAPH_ENABLED=0
    HADOOP_ENABLED=0
    Note: Alternately, you can omit the other start up entries and just use SPARK_ENABLED=1.
  2. Start DataStax Enterprise:
    $ sudo service dse start
    Starting DataStax Enterprise as a service runs a script that sets up the environment and launches the DSE service. After the DSE service is launched, the script verifies if the service is running. It is possible for the DSE service to take a few seconds to start, and this error might display:
    WARNING: Timed out while waiting for DSE to start. 
    However, this error does not necessarily mean that the DSE service failed to start. Check the log files, for example /var/log/cassandra/system.out.
  3. To wait longer until the service is declared not to launch successfully, you can change the number of times to check if the DSE service is running. The DSE start script checks if the DSE service is running once per second, so the number of checks is equal to the number of seconds. To configure the number of times to check if the DSE service is running, uncomment and edit the WAIT_FOR_START option in the /etc/default/dse file, and then restart the DSE service:
    # Uncomment if you want longer/shorter waits checking if the service is up
    WAIT_FOR_START=14
  4. To check if the cluster is running:
    $ nodetool status

    On Enterprise Linux systems, the DataStax Enterprise service runs as a Java process.

    Note: If you have trouble, see Troubleshooting starting DataStax Enterprise.

    The nodetool command shows the node type and the status. For a Cassandra node running in a normal state (UN) with vnodes enabled shows:

    Datacenter: Cassandra
    =====================
    Status=Up/Down
    |/ State=Normal/Leaving/Joining/Moving
    --  Address    Load       Tokens  Owns    Host ID                               Rack
    UN  127.0.0.1  82.43 KB   128     ?       40725dc8-7843-43ae-9c98-7c532b1f517e  rack1

    For example, a running node in a normal state (UN) with DSE Analytics without vnodes enabled shows:

    Datacenter: Analytics
    =====================
    Status=Up/Down
    |/ State=Normal/Leaving/Joining/Moving
    --  Address         Load       Owns    Host ID                               Token                 Rack
    UN  172.16.222.136  103.24 KB  ?       3c1d0657-0990-4f78-a3c0-3e0c37fc3a06  1647352612226902707   rack1